core/sql/refresh/RuMultiTxnContext.cpp

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/* -*-C++-*-
******************************************************************************
*
* File:         RuMultiTxnContext.cpp
* Description:  Implementation of class CRUMultiTxnContext.
*				
*
* Created:      08/17/2000
* Language:     C++
* 
*
* 
******************************************************************************
*/

#include "RuMultiTxnContext.h"
#include "dmresultset.h"

//--------------------------------------------------------------------------//
//	PUBLIC METHODS
//--------------------------------------------------------------------------//

//--------------------------------------------------------------------------//
//	CRUMultiTxnContext::ReadRowsFromContextLog()
//  This function fills the stack with context from the UMD
//  table 
//--------------------------------------------------------------------------//

void CRUMultiTxnContext::ReadRowsFromContextLog(CDMPreparedStatement *readStmt)
{
	RUASSERT(NULL != readStmt);
 
	try
	{
		// The rows are sorted by BEGIN_EPOCH asc

		CDMResultSet *pResult = readStmt->ExecuteQuery();
		
		while (pResult->Next()) 
		{
			const Int32 kEpoch  = 1;
			
			stack_.AddHead(pResult->GetInt(kEpoch));
		}
	}
	catch (CDSException &ex)
	{
		ex.SetError(IDS_RU_FETCHCTX_FAILED);
		throw ex;	// Re-throw
	}

	readStmt->Close();
}

//--------------------------------------------------------------------------//
//	CRUMultiTxnContext::GetRowByIndex()
//
// This function return ROW_DOES_NOT_EXIST if no such row exists
//--------------------------------------------------------------------------//

TInt32 CRUMultiTxnContext::GetRowByIndex(Lng32 index) 
{
	RUASSERT(0 <= index);

	if ((stack_.GetCount() <= index))
	{
		return ROW_DOES_NOT_EXIST;
	}
	
	DSListPosition pos = stack_.FindIndex(index);

	return stack_.GetAt(pos);
}